Context is helpful here. Reference this article from Dave Tate regarding timed movements at Westside Barbell (in this case, the dumbbell press)
"Timed Dumbbell Presses
_This is the latest news out of Westside Barbell Club. Louie Simmons has found that taking a pair of dumbbells and pressing for time to be a great strength and restoration builder for the bench press. He’s been using a three-day split where the first day heavy dumbbells would be used continuously from two to four minutes. I’ve used up to 80-pound bells for three minutes. _
These reps aren’t done in a non-stop action. (Had you scared there for a second, didn’t I?) You do a couple of reps, then hold them on your chest or at the top for five to ten seconds, then do a couple more reps. You keep the set going until you can’t do any more. Perform only one set at the end of the regular workout.
_On the second day you want to use 60% of the weight used on day one, but take the time up to three to five minutes. I use 45 pound dumbbells for this day. On day three, drop another 60% and bump the time up to five to eight minutes. On this day, I use 25 to 30 pound dumbbells. _
I’ve found this to help my shoulders recover at a faster rate than when not doing them. While Louie likes to keep the rotation going without a break, I like to only use the rotation one time per week."
Emphasis mine. Most likely it was in a similar capacity with the box squats.